Altera PowerPlay Early Power Estimator User Manual
Page 51

Figure 3-28: Enpirion Worksheet of the PowerPlay EPE Spreadsheet
Table 3-17: Enpirion Worksheet Information
Column Heading
Description
Group
Compatible rails are combined in order to minimize
the number of regulators required. For additional
information, refer to the Report worksheet. See also
Grouping Errors on the Main worksheet.
Regulator Input Voltage (V)
Enter the input voltage here. The output voltage will
be derived from this voltage. This field is filled
automatically when non-zero Parent Group is
specified.
Load Current Margin
Margin can be added to account for component
variability. It is recommended to retain the default
30% to assure the thermal capability of the solution
over the full range of device variation and operating
conditions. However, in certain cases when
characteristics and conditions are fully defined,
reducing the margin may lead to a more cost-
effective solution. Exercise caution when changing
these values.
Parent Group
If one of the group voltages is to be used as an
intermediate bus voltage, enter the group number
here.
Regulator Type
In some cases, a linear regulator (LDO) may be a
good choice to supply one of the group voltages.
The efficiency of an LDO is the ratio of output
voltage to input voltage. In the figure, Group 2 can
be efficiently supplied by an LDO. If desired, select
Linear in the row for Group 2.
POK
Select Yes to select a regulator with a Power OK
(POK) output to assist with sequencing.
UG-01070
2015.01.20
Enpirion Worksheet
3-41
PowerPlay Early Power Estimator Worksheets
Altera Corporation